Effects of family, seed position and burial depth on seed emergence of Ligularia virgaurea

Ligularia virgaurea is a wellknown poisonous weed in the alpine meadows of the eastern QinghaiTibet plateau. The effect of temperature on seed germination under darkness conditions in a laboratory experiment and the effects of family, seed position and burial depth on seed emergence in pot experiments were studied. The results showed that the effect of temperature on germination percentage was significant and the germination rate decreased with the temperature rising. It was 87.33% while temperature was 18/28 ℃ and 95.33% while the temperature was 5/15 ℃. The emergence percentage was the highest (61.66%) while the burial depth was 0 cm. And it tended lower while the burial depth was 3 cm and was 0 while the burial depth was 5 cm.